Yamaha WR250R Mega Thread

I was thinking the same thing!.....

Some of you Northwesterners might like this one as well. It's the 1st one I created.


You won't want to make it any smaller than 6" wide.

Click for larger image.

I ran this through a vector program to clean up the aliasing (aka jagged edges) and saved it as an eps file. An eps file can be resized and look the same. A lot of vinyl cutters can take this as an input too.


nw03di3.eps


Here's a preview without the jagged edges:



(not bad for a techie but maybe a graphics guy could clean it up more )

Keeeewl. Want. NJ Want.

PM sent

Well, the howling wind finally died last night and I was able to complete my sound measurements this morning. By the way, I'm not sure how the rest of the country faired, but some kind of double bad Northern blew through Oklahoma like a freight train. Sunday afternoon it was a balmy 76 degrees, then 6 hours later it was 25 degrees! :eek1 Anyway, I digress....

For you Technomaniacs, I followed the sound testing procedure covered in this link: http://www.thumperfaq.com/sound.htm

Well, as best I could anyway. Kind of hard to do it perfectly without a tachometer. Here's a photo of my sound meter in action, which anyone can buy from Radio Shack. Its an affordable, accurate unit. I've had lots of practice with it as the Sound Engineer at my Church. It works!





I don't know if I was below, at, or above the rpm for 1/2 peak power. Don't really care. Who knows how the manufacturers actually rate their products. Since I didn't have a Tach on R², I had to devise a plan for consistency to easily apply to each bike. So, while the actual measured numbers may be different than manufacture ratings....or even some official certified field test....I think they are decent comparisons between each bike.

I measured sound at the following points:
1) Idle
2) 1/4 throttle
3) 1/2 throttle

No, I didn't get all scientific and physically measure/mark these exact points on the throttle for each bike and hold it there perfectly. I just turned it to where I felt was right. If you want it better, do it yourself!

Drum Roll........here are my results:

Pipe- Idle- 1/4- 1/2

Stock w/ SA- 90- 103- 105
Stock w/ Graves- 93- 105- 110
Powerbomb/Q4- 91- 104- 107

KLX250 w/ Q2- 94- 99- 107

Interesting results on paper. Everyone knows the sound of the stock pipe. It is definitely more quiet to the ear than the Q4, but actually produces similar measurements. At least not as far off as you'd think. The differences in my numbers could easily be related to throttle position...due to my unscientific method.

I can tell you the sound of the Q4 is definitely different. The Graves Insert and the Q4 both produce a deeper tone of sound. Maybe that is what we usually interpret as being "louder". I know that I felt I could sneak around in stealth mode with the stock pipe & can. But I do not think that I could go undetected with the Q4. Maybe its all in my mind while I'm sitting on the saddle and not such a big issue from a distance. I donno.

I do know Zadok's Powercore seems louder than my Q4. But, it was too windy to test his the other day. We'll post that result later....

HF

Thanks for the comparison HF.

Had a feeling a DB test would show that the Q4 is
really not that loud - just more of a different
pitch/frequency than the stocker.

FMF rates it as 92db in their description.

I don't know how accurate that could be. In a season of AMA Db testing I have yet to test a MXer (with any of the thundering exhausts from FMF, Pro Cir, WB, etc.), at higher than 102 Db at 50% max RPM.

For comparisons sake, AMA MX sound at 50% max RPM is now 96 Db. =/-1. No way a stock or Q4 piped bike is near/over 100 Db!!! The Q4s we tested were all at or below 92 Db, 20" from tip of muffler.

Actually that's part of the cutting process. When you're ready to cut/plot the image it's vectorized first. Also the image is very large...When scaled down for actual printing there no concern regarding jagged edges (at least it hasn't been for this particular graphic).

Guess which wannabe lurker (well, mostly lurker) has finally joined the club.....



Just before winter can be a good time to find some deals. This one was a Yamaha demo bike that was on loan to a local trail riders organization. Way cheaper than list, a few nice add-ons and a 3/4 warranty to boot!

Sure is gonna make for a long winter though..

HF, I don't care how scientific or accurate your tests are, it's the deltas that are interesting. Looks like the Q4/powerbomb combo does pretty well compared to stock - looking forward to hearing your general impression of sound levels once you've had a chance to live with it a bit. btw, thanks for your comments on the stabalizer... food for thought.

Just saw over on TT that someone emailed Scotts.

"Dear Customer,



We are <NOBR>working</NOBR> on it. We should have this completed at
the first of the year. If you leave me your number we can
call you when it is completed.



Thank You,

Jake

Scotts Performance

818-248-6747"<!-- / message -->

Just in time to go with those new gas tanks.

FANTASTIC Gordo!!! And it even got a tailrack already.
I waited 2 months for mine!
And she's even got a "butt tuck".
Forget the cold....go ride!

Regarding my sound test, I agree with you about the "deltas". You can see my measurements were at least reasonably consistent. I have no idea why the readings were so high. I did everything to spec...except measure rpm with a Tachometer. I was 20" from the exhaust port, perpendicular to a line on a 45 degree angle. Exactly like the diagram in the "Link" I referenced. Maybe I was reving too high. But, I sure could make the bike "still go higher" by cranking more throttle.

I checked rpm versus throttle opening on my KLR first. It has a Tach. Got about 4,000 rpm with 1/4 throttle and about 8,000 rpm with 1/2 throttle (in Neutral). I did the same thing on my son's KLX 250 and produced similar results. So, I figured I had a good enough reference point for general rpm level (in Neutral). Just a self-determined Rule of Thumb.

I just finished a Dyno test, so I know peak power is around 8,000 rpm (+/-). It seemed reasonable to conclude that 1/4 throttle would generate something close to 50% of Peak Power. Again, I'm not so concerned with actual decibel level as I am with the differences between the measurements. Its not like this is a hard, complicated procedure. Its quite easy to do, actually.

FIDOLLAZ...... Since you've performed real field test on MXer's all season long, I'd like to know a little more about your actual procedure. How did you establish a consistent point for 50% of Peak Power on so many different bikes....all of which don't have Tachs? Did you attach one of those vibrating - magnetic tachs, or what? How much throttle turn was typically related to your measurements? Tell me how to correct my process....and I can easily repeat the test. Otherwise, send me your equipment, I'll use it to measure same way you do, and then send it back to you. Beyond that, oh well...

ScottMac, how did they do the field test for your event? Position, throttle turn, etc?

HF

Hey HF. Your sound readings seem high. I helped with the sound tests at the AMA ISDE qualifiers we had at the Zink ranch years ago. Several things affect the readings. Any Wind will give you very high readings. Where you stand affects the meter. You should be standing next to the footpeg/seat area as close to the bike as possible with you back towards the front wheel. If you are standing beside the muffler, sound will bounce off you and give higher readings. ANYTHING that vibrates on the bike can peg the meter. Exhaust springs, flapping side panel, a footpeg rattling around. Many aftermarket mufflers are very thin and the thin metals vibrates and rings. Even though we can barely hear it, it will send the meter way up. Many riders would put a boot on the exhaust to absorb the vibration. This WOULD lower the readings remarkably. Air cooled bikes can't hardly pass a sound test because of the cylinder fins ringing. ..........Happy Trails!!!




p.s. We used those virbating tachometers. We were told by the AMA that they were the most accurate.

Well HF you just can't win with this audience I guess.
The jury has spoken and your dyno readings are too low and your sound readings are too high.
Funny that your specific numbers get challenged so much, while other people review things and just post generalizations with no quantitative support and no one makes a peep.

It doesn't matter to me if the dyno (or sound level meter) was calibrated, and it doesn't even really matter to me what method you used for the tests.
The point is, if you use the same meter (or dyno or whatever) and the same method then we are able to make some really good comparisons between stock and modded bikes.

Thanks again for taking the time to gather the numbers.


Congrats on the bike Gordo! Great find.
What, might I ask, is in that cage?

HF, if you re-do the sound comparo, please consider making audio recordings as part of it. Say a 10-second sample at whatever settings you measure at anyway.

Then I (or you, or anybody) could download them and load them into something like Audacity, and compare levels, where the power in the spectrum is, stuff like that. Oh, and listen to them too.

Well, maybe not how I want to- no R² (yet, or for a while) but to go back a day or so, I used to race bicycles. My Castelli bike shorts (bibs) were the best I ever used, and lasted the longest- they're not cheap though! Pearl Izumi were ok, and much cheaper. Louis Garneaux were marginally better than PI, but didn't fit my body as well. The chamois in the Castelli was the softest, most flexible, and most comfortable, even on the tender nether regions after a 4+ hour day in the saddle.:huh

Hope this can help some.

While I'm here, how feasible does the Collective think it would be to pack up the R² for some light touring- what kind of weight limitations would you say the lack of substantial subframe poses? Could a ~11 pound tent, plus pad, sleeping bag, light weight stove, and a few days' worth of food and clothing be safely/comfortably carried, to make minimalist touring possible? I'm looking for excuses to make the R² my everything bike, commute daily year round, fun ride, and light tour. I think it could be so much more than a KLR!

[returns to pipe-dreams of riding, prlly a year off still due to job/family]

Jeremy

Shit, you had to ask eh? Now I have to post up on a motorcycle forum and confess to owning a friggin' bunny rabbit.

Oh ya, think that's funny? Don't underestimate these things, they're really quite dangerous! Typical low lying wires have a survival rate of about 10 sec, often less! We're pretty good at keeping it at bay, but the first year was quite harrowing. :eek1 They truly are to be feared and avoided at all costs!

Thanks CM and HF.

I thought the subframe looked overbuilt. I expected it to be aluminum, not a steel ladder design. Service manual lists a max rider/cargo weight of 408lbs. In about a month I should have racks mounted, at which point I intend to find the stuff-carrying limits the hard way. And by hard way I mean fun way.

Yes, well said. We should be giving this guy a medal for spending his own money and doing all this research and instead he's getting a bunch of crap. As long as HF keeps doing repeatable tests with the same bike and same measuring equipment, I'll be stuck reading this thread every night.

Is kind of interesting isnt it? HF takes the time to do the testing,
then more time to post results, and then he gets jumped for
"not doing it right".

Just makes you wonder why those same people dont just go
do it the "right way" themselves......Oh yeah, it takes time
and money.

I know HF, and I will say he enjoys doing the comparisons
and testing. But at the same time, he doesnt have to
take the time to share either.

Thanks HF, interesting numbers on the differences between
those. It will be interesting to see where my Powercore 4
is in that lineup.